Clinical and Radiographic Assessment of Lumbar Spine Total Disc Replacement in Athletes with Two Year Follow Up

by McRae, Mark H.

The purpose of the study was to evaluate the consequences of athletic activity on the clinical and radiographic outcomes of lumbar spine total disc replacement (TDR) patients. The data for this study is drawn secondarily from a prospective randomized study evaluating the Prodisc prosthesis at Yale New Haven Hospital. Athletic activities prior to the onset of spinal injury, after the onset of spinal injury, and post lumbar spine total disc replacement (TDR) surgery were assessed. Athletic activity was classified into three groups. These were contact/vigorous, moderate, and light, based on effect on the involved spinal segments. Outcomes were assessed both clinically and radiographically. Out of 195 patients enrolled in the Prodisc study at Yale, 82 qualified for inclusion and fulfilled all follow-up criteria. In these 82 patients 120 disc replacements were performed. The average reduction from pre-operative visual analog pain scale was 44 (std dev 30.1) at a minimum of 2 years follow up. The average reduction in Oswestry disability index was 38% (std dev 23). 74/82 patients returned to athletic activity following TDR. 19 (23%) patients returned to pre-injury athletic activity levels, 47 (57%) returned to athletic activity but not to pre-injury levels, 14 (17%) patients reported activity levels that were unchanged since surgery, and 2 (3%) had activity levels become more impaired since surgery. Of those that returned to athletic activity, 4/74 complained of radiculopathy symptoms during athletic participation. Overall, 14 of 82 patients reported persistent back pain and 8 of these patients reported radiculopathy symptoms. Segmental flexion and extension at the levels of the implant, and the levels adjacent, revealed that the goal of physiologic motion was not reached at either the level of the implant, nor at the superior or inferior adjacent segments. Three L5/S1 subluxations occurred in heavy weight lifters and were the only radiographic complications. Athletic activities of varying degrees appear to be well-tolerated following lumbar TDR surgery in single and multi-level cases. Contact-vigorous athletic activities do not appear to result in high levels of clinical or radiographic complications in the lumbar TDR patients except for heavy weight lifting activities in patients who have undergone L5/S1 Prodisc surgery in which we experienced 3 implant subluxations. Further biomechanical and clinical studies are necessary before general recommendations can be made.